Upvote:6
No airport I've ever seen offers this as a (free) service.
However many airports have 3rd party companies located on airport property that offer is as a paid service.
Why? For exactly the same reason that most airports have a shop that sells coffee - because customers are willing to pay for it! If customers were not willing to pay for these services (be it either luggage wrapping or coffee!) then these shops would not make money and would close - but the fact they exist shows that's not the case!
Upvote:10
They offer this service because people are willing to pay for it. Whether or not it accomplished their goals is a different story.
It can be used to protect the bag from external things like rain, the belts, etc. It can be use to protect the appearance of the bag, to make it last longer. I also get the feeling that it's a cultural thing in some regions.
Keep in mind, if the airline, airport security, Customs, etc. wants to examine the bag, the plastic wrap will not stop them in the slightest.